Internal combustion engines, or more particularly, gas fueled engines, may be used to power various different types of machines, such as on-highway trucks or vehicles, off-highway machines, earth-moving equipment, generators, aerospace applications, pumps, stationary equipment such as power plants, and the like. In general terms, gas fueled engines are supplied with a mixture of air and fuel, which is ignited at specific timing intervals using spark plugs and ignition systems in order to generate mechanical energy, such as rotational output torque, and ultimately used to drive or operate the associated machine. There are various ongoing efforts to improve the efficiency and reliability of the engine, and the overall productivity of the machine. Periodically monitoring the health of spark plugs is one way to help reduce unplanned downtimes and improve productivity.
The life of a spark plug in an internal combustion engine may be affected by the magnitude of the electrical current that is repeatedly passed across a gap of the spark plug. In particular, the repeated exposure to high electrical current may subject the metal tip of the spark plug to various failures over time. Over time, for instance, a spark plug may be prone failures caused by metal erosion at the tip or near the spark plug gap, delamination at the metal tip, spontaneous detachment of metal at the tip, or the like. When left unaddressed, such failures may result in misfires and other adverse effects which can decrease overall efficiency of the machine or cause engine damage. It is thus helpful to not only be able to track the health of the spark plugs, but also to be able to quickly detect failures when they occur so as to minimize inefficient operation, unplanned downtimes and unnecessary damage.
One currently available means for detecting spark plug failures is disclosed by U.S. Pat. No. 6,559,647 (“Bidner”). Specifically, Bidner discloses a method which temporarily disables one of the spark plugs in each cylinder of the engine during a designated test period, in order to determine whether a misfire occurs. Based on whether a misfire occurs, Bidner is able to confirm proper functionality of each spark plug. Although Bidner may be effective, it can become quite tedious to disable each spark plug for each cylinder of each engine, and it can also be quite time consuming to complete each test routine. Furthermore, because the test routine in Bidner cannot be performed on the fly or during normal engine or machine operations, the total amount of downtime set aside and spent on running such tests throughout the life of the machine can be substantial.
In view of the foregoing disadvantages associated with conventional spark plug monitoring techniques, a need exists for a solution which, not only effectively monitors for spark plug failures, but also does so passively, without interrupting productivity and without requiring any significant downtime. Moreover, there is a need for a spark plug monitoring technique that is capable of employing readily available data and information, such as from an engine control or management unit, and using that information to identify the health or any existing failures in the spark plugs. The present disclosure is directed at addressing one or more of the deficiencies and disadvantages set forth above. However, it should be appreciated that the solution of any particular problem is not a limitation on the scope of this disclosure or of the attached claims except to the extent expressly noted.